Cambridge Vascular Unit, Cambridge University Hospitals NHS Foundation Trust, UK.
Eur J Vasc Endovasc Surg. 2010 Apr;39(4):418-28. doi: 10.1016/j.ejvs.2010.01.001. Epub 2010 Feb 1.
Contrast-enhanced computed tomography (CT) has become the 'gold-standard' imaging modality for surveillance following EVAR. However repeated CT causes cumulative contrast related renal injury. Duplex ultrasound (USS) and contrast-enhanced (non-nephrotoxic) duplex scanning (CEUS) are less invasive but considered less accurate than CT. The aim of this study was to determine the diagnostic accuracy of imaging modalities used to detect endoleak. Accordingly, we undertook a systematic review and meta-analysis of the evidence base for USS and CEUS compared to CT following EVAR.
Medline, Embase, trial registries, conference proceedings and article reference lists were searched to identify trials comparing USS or CEUS with CT following EVAR. Contrast-enhanced computed tomography was taken as the 'gold-standard' investigation. USS and CEUS were compared to CT in separate meta-analyses.
Twenty-one studies in 2601 patients compared USS with CT. The sensitivity of USS at detecting endoleak was 0.77 (95% CI 0.64-0.86; I(2)=0.82) and pooled specificity 0.94 (95% CI 0.88-0.97; I(2)=0.90). Seven studies (288 patients) compared CEUS vs CT. The pooled sensitivity was 0.98 (95% CI 0.90-0.99; I(2)=0.32) and specificity 0.88 (95% CI 0.78-0.94; I(2)=0.67).
This study confirms that unenhanced USS has poor sensitivity for endoleak detection; however CEUS is a highly sensitive modality. These results should be interpreted with some caution due to heterogeneity in analysed trials and further research is needed to evaluate the efficacy of CEUS before it can be utilised as the primary imaging modality for EVAR surveillance.
增强计算机断层扫描（CT）已成为 EVAR 后监测的“金标准”成像方式。然而，重复 CT 会导致累积的对比相关肾损伤。双功能超声（USS）和增强（非肾毒性）双功能扫描（CEUS）侵袭性较小，但被认为不如 CT 准确。本研究旨在确定用于检测内漏的成像方式的诊断准确性。因此，我们对 EVAR 后 USS 和 CEUS 与 CT 进行了系统评价和荟萃分析。
通过检索 Medline、Embase、试验注册处、会议记录和文章参考文献列表，确定了比较 USS 或 CEUS 与 EVAR 后 CT 的试验。以增强 CT 作为“金标准”检查。在单独的荟萃分析中比较 USS 和 CEUS 与 CT。
21 项研究纳入 2601 例患者，比较 USS 与 CT。USS 检测内漏的灵敏度为 0.77（95%CI 0.64-0.86；I²=0.82），特异性为 0.94（95%CI 0.88-0.97；I²=0.90）。7 项研究（288 例患者）比较了 CEUS 与 CT。汇总的敏感性为 0.98（95%CI 0.90-0.99；I²=0.32），特异性为 0.88（95%CI 0.78-0.94；I²=0.67）。
本研究证实，未增强 USS 对内漏检测的敏感性较差；然而，CEUS 是一种高度敏感的方法。由于分析试验的异质性，这些结果应谨慎解释，需要进一步研究来评估 CEUS 的疗效，然后才能将其用作 EVAR 监测的主要成像方式。
